This invention relates to a support and coupling assembly in a screw conveyor and particularly a screw conveyor used in the blast cleaning industry. Typically a screw conveyor comprises at least first and second screw conveyor lengths which are aligned axially along an axial axis. There is a need to support the two lengths of screw conveyor and to couple the two lengths together.
In the past, there have been different types of devices used to support or couple the lengths of screw conveyor. However, none of those devices seem to have worked satisfactorily, especially when the screw conveyor was used to move blast cleaning shot in the blast cleaning industry.
Typically, lengths of screw conveyor are about 10 to 12 feet in length. The screw conveyor lengths are rotated relatively slowly by a motor. The conveyor lengths have screw flights which rotate as the screw conveyor length rotates and thereby move the material intended to be moved.
It is necessary to support the ends of the lengths of screw conveyor and to transfer the rotation of the first length of screw conveyor into rotation of a second length of screw conveyor. However, over the length of 10 or 12 feet there is some considerable deflection of the ends of the screw conveyors off the axial axis. In some cases, this deflection can be one-half inch to one inch or more.
The past devices used to support and couple screw conveyor lengths were typically rigid and difficult to assemble. Also, these devices were prone to break-down caused to a large degree by the deflection of the ends of the screw conveyor lengths, and it was difficult to replace broken parts. Also, there was a considerable gap or distance between the first screw conveyor length and the second screw conveyor length such that at least some of the material intended to be moved by the screw conveyor would fall or drop onto and into the various components of the prior art devices, thereby leading and contributing to break-down of the prior art devices.
Accordingly, it is an object of this invention to at least partially overcome the disadvantages of the prior art. Also, it is an object of this invention to provide an improved support and coupling assembly in a screw conveyor, particularly a screw conveyor in the blast cleaning industry.
Accordingly, in one of its aspects, this invention resides in providing a support and coupling assembly in a screw conveyor comprising first and second screw conveyor lengths aligned axially along an axis, the assembly comprising a first deflection-accomodating means for accommodating deflection off the axial axis between the first screw conveyor length and the second screw conveyor length; second deflection-accommodating means for accommodating deflection off the axial axis between the first screw conveyor length and the second screw conveyor length; first connecting means for connecting the first deflection-accommodating means to the first screw conveyor length; second connecting means for connecting the second deflection-accommodating means to the second screw conveyor length; a drive shaft connecting the first deflection-accommodating means to the second deflection-accommodating means; and support means for supporting the drive shaft; wherein the first deflection-accommodating means comprises an outer member aligned axially and concentrically with the first length of screw conveyor along an axial axis, and having an outer diameter substantially the same as the outer diameter of the first screw conveyor; an inner member aligned axially and concentrically within the outer member along the axial axis, and having an outer diameter greater than the outer diameter of the drive shaft; a first plurality of blades wherein each blade extends radially inwardly from the outer member and axially along the outer member; a second plurality of blades wherein each blade extends radially outwardly from the inner member and axially along the inner member; wherein the blades of the first plurality of inwardly-extending blades are spaced alternately with and angularly from the blades of the second plurality of outwardly-extending blades to form angular spaces between blades; and a resilient material in the angular spaces between blades; wherein the second deflection-accommodating means comprises an outer member aligned axially and concentrically with the second length of screw conveyor along the axial axis, and having an outer diameter substantially the same as the outer diameter of the second screw conveyor; an inner member aligned axially and concentrically within the outer member along the axial axis and having an outer diameter greater than the outer diameter of the drive shaft; a first plurality of blades wherein each blade extends radially inwardly from the outer member and axially along the outer member; a second plurality of blades wherein each blade extends radially outwardly from the inner member and axially along the inner member; wherein the blades of the first plurality of inwardly-extending blades are spaced alternately with and angularly from the blades of the second plurality of outwardly-extending blades to form angular spaces between blades; and a resilient material in the angular spaces between blades; wherein a first end of the drive shaft is fixed within the inner member of the first deflection-accommodating means; wherein a second end of the drive shaft is fixed within the inner member of the second deflection-accommodating means; and wherein the support means comprises a support bearing supporting the drive shaft intermediate of the first end and the second end of the drive shaft and a support member supporting the support bearing to a fixed object.
Further aspects of the invention will become apparent upon reading the following detailed description and drawings which illustrate the invention and preferred embodiments of the invention.